President Jimmy Carter applauds as Sen. Edward Kennedy waves to cheering Democratic National Convention delegates in New York’s Madison Square Garden, Aug. 14, 1980. Kennedy’s vigorous primary challenge contributed to Carter’s eventual loss to Ronald Reagan that fall.

President Jimmy Carter applauds as Sen. Edward Kennedy waves to cheering Democratic National Convention delegates in New York’s Madison Square Garden, Aug. 14, 1980. Kennedy’s vigorous primary challenge contributed to Carter’s eventual loss to Ronald Reagan that fall